Process for producing superior motor fuel



Aug- 26, V1952 PQH. JOHNSON ErAL PROCESS FOR PRODUCING SUPERIOR MOTORFUEL Filed May 7. 1948 Patented Aug. 26, 1952 PROCESS FOR PRODUCINGSUPERIOR MOTOR FUEL raul Hilton Johnson, Bartlesville, Okla., .and GlennJ. Forseth, Spring Valley, Wis., assignors to Phillips PetroleumCompanys@ corporation of Delaware Application May 7, 1948, Serial No.25,594

(Cl. 196;. 5m`

l` Claims. 1

This invention relates to a process for the manufacture of an improvedmotor fuel. In one of its more specific-aspects, it relates to a processfor the manufacture of motor fuels for internal combustion origines.V Ina preferred embodiment,

this invention relates, to the manufacture of an automotive gasolinefuel .of superior road nat- It is Well knownthat in actual use, motorfuels of similar octane number will often give widely varyingperformance. The reason that the superior qualities of certain `motorfuels do not show up in the laboratory is due tothe inadequacy of thepresent testing methods.` "It is generally considered that a motorofuelVwhich Will knock the least is superior,` and knocking is most apparentwhen an automobile is being accelerated 'and when the load `on theengine is constantly changing. The knocking tendency of fuels as theyare tested in the laboratory is determined with a motor operating. atarelatively constant speed and at a constant load. Therefore, knockingdata relative to acceleration` and changing load are not obtained. Thus,the, only entirely satisfactory testing method known at the present timeis in stock automoblleengines under conditions of actual rcadratingtesti.` e. driving the automobile and actually` determining how the motorfuel acts under allroad conditions. This type of test gives conclusivedata as to the value of a motor fuel in actual service.

By such road rating tests, it has been determined that the variation inperformance of inotor fuels of the same octanenumber is dependent to agreat extent "onthe olefin content. It has been found that motorfuelscontainingsubstantial amounts of olefin hydrocarbons in the low boilingrange and substantial amounts of aromatic, iscparaffinic,` and/ornaphthenic hydrocarbons in the high boiling range produce superior lowand high `speed performance in lnternal combustion engines of the typeused in automobiles. the maximum boiling point of the olenic componentsshould not be in-excess of about 250 F., the approximate mid-boiling'point of gasoline motor fuel. The idealfuel then, might be presumed toconsist `of approximately 50 per cent olens boiling below 250 F. and 50vper, cent aromatic, isoparainic, and/or naphthenic materials boilingrabove 250 F, i

Broadly speaking, our invention comprises a single step catalyticcracking process for the manufacture of a superior road rating motorfuel. We have discovered that a `mixture of Further, it has been foundthatl naphthenic naphtha and heavy gas oil contacted with a suitabledehydrogenation-cracking catalyst, such as bauxite, which will causedehydrogenation, cracking, and aromatization, produces a superiorautomotive fuel.

In this specification, the term in'aphthenic naphtha as 'referred tomeans a mixture which includesa substanital proportion of thosehydrocarbons known as naphthenes or cycloparaffins. By definition,naphtha is a mixture ofilowboiling hydrocarbons and is a term well knownto those skilled in the art. Also used in this specification is the termgas oilff This may be either a virgin or synthetic gas oil which is asuitableA cracking stock. i

`In accordance with our invention, a mixture `of naphthenic naphthacomprised of cyclic parafiins having a boiling range of 250 to 400 F.and a'gas oil comprised primarily of paraflins boiling infthe rangeof'450 to 750 Rin a ratio of naphtha-to gas oil'of 1:5 to 5:1, however,preferably within the 'range of 1:2 to 2:1, is contacted under crackingconditions with a suitable dehydrogenation-cracking catalyst such asbauxite. The naphtha-gas oil mixture is charged to a suitable `crackingunit lat a temperature in the range of 800 to 1l00 F., but preferablybetween 900 and 1050 F., e. pressure in the range of 0 to 300 pounds persquare inch, but preferably between-20 and 100 pounds per square inch,and a space velocity of from 0.5 to`5 liquid volumes of charge pervolume of catalyst per hour. The total eiiluent from the crackingreaction is fractionated by suitable fractionation mea-neto separate thenormally gaseous materialsyfa superior road rating motor fuel, and heavymaterials boiling above 400 F. which may be wholly orinar- 'tiallyrecycled as desired.

The action of the catalyst on the charge stock is primarily one ofAcracking, dehydrogenation, andaromatization; The gas oil by thistreatment cracked `and dehydrogenated, thereby forming a predominance ofolensboiling below the mid-boiling point of gasoline. The naph-`thenic-naphtha portion ofthe charge stock `beying inherently somewhatrefractoryis partially aromatized, thus giving both aromatics andnaphthenes as products.` The aforesaid fractionation of thetotal'eiiluent produces a gasoline boiling range fraction of which thelow-boiling half is comprised primarily of oleflns and thehigher-boiling half primarily of aroma-tics and `naphthenes.` Thiscatalytic treatment of the naplithenic naphtha produces only very mino-riportions'of paraiiins and oleiins.`

Conventional catalytic cracking equipment is satisfactory for theoperation of this invention. Suitable means should be provided formaintaining the desired temperatures, pressures, and other conditionsrequired by the process in the various Zones.

An object of this invention is to provide a process for manufacturing asuperior motor fuel.

Another object is to provide a method for producing an improved motorfuel having a high road rating at all speeds.

Another object of this invention is to provide a method formanufacturing an improved motor fuel which exhibits superior performancecharacteristics over the entire speed range, in an internal combustionengine, particularly during periods of acceleration.

A further object is to provide a method for manufacturing a superiorinternal combustion engine fuel from naphthenic naphtha and heavy gasoil.

A further object is to provide a method for producing a superior motorfuel by a catalytic process.

A further object is to provide a one step catalytic process for themanufacture of motor fuel.

A further object is to provide a method for manufacturing a superiorroad rating motor fuel by -catalytically treating a mixture ofnaphthenic naphtha and gas oil.

Further objects and advantages of this invention will be apparent to oneskilled in the art from the accompanying disclosure and discussion.

A better understanding of some ofthe many aspects of our invention maybehad by referring to the attached schematic iiow diagram in conjunctionwith the following discussion. It is understood that While this isrepresentative in general of our process, various minor changes may benecessary in adapting it to the various conditions Within the scope ofthe invention.

Naphthenic naphtha and steam (20 to 100 pounds per barrel of hydrocarbonfeed) or other diluent are introduced into line I2 through lines I andIi, respectively, where they are admixed with heavy gas oil introducedthrough line I2. The hydrocarbon-'diluent mixture passes via line I2through preheater I3 and is introduced to catalytic cracking zone I4 ata temperature in the range of 800 to 1l00 F. and a pressure in the rangeof 0 to 300 pounds per square inch. The mixture is contacted with asuitable catalyst, such as granular, calcined bauxite, which will causedehydrogenation, cracking, and aromatization. Effluent from catalyticcracking means I4 is passed through line I5 to separation means I6.Light gases are removed through line Il, gasoline through line I8, waterthrough line I9, and heavy residue through line y2l). If desired, theheavy residue may be removed through the outlet in line 20 or recycledthrough lines 2I and I2 and preheater I3 to catalytic cracking means I4.

Advantages of this invention are illustrated by the following example.VThe reactants and their proportions, and other specic ingredients arepresented as being typicaland should not be construed to limit theinvention unduly.

Example in the range of 458 to '725 F. Column 2 shows the properties ofa gasoline produced by treating a 250 to 400 F. straight-run naphthenicnaphtha. Column 3 shows the properties of a blend of the gasolinesproduced in runs l-and 2, properties of which are shown in columns 1 and2. Column 4 gives the properties of a gasoline vproduced by treating a1:1 blend of the gas oil and naphtha used in runs 1 and 2.

Column 1 2 3 4 ASTM Distillation, F.:

IBP l 99 137 115 119 5% evap. 760 mm 124 220 162 164 10% 139 247 190 19150% i l i 252 309 296 299 365 361 259 307 P 402 408 396 408 ASTM OctaneNumber 0 cc. TE l 77. 0 46. 6 57. 8 60.9 1 cc. TEL 79. 5 56.0 65. 5 67.8 3 cc. TEL 81.3 65.7 73.1 73.8 Research Octane Number: v

TEL .1 48.5 60. 4 63. 5 55. 9 69. 1 7l. 1 68. 4 77. 6 78. 7 52. 7 53.853. 2 Brominc Number 9 33 34 A comparison of the above data shows animprovement inthe ASTM and Research octane number of the productgasoline from the combined treatment of the gas oil and naphthenicnaphtha over that of the product of the separate treatment ofthenaphtha, or a combination of the products of the separate treatment ofthe gas oil and naphtha. The separate treatment of the gasoil providesthe highest octane numbers of all, but it also shows a too high per centof olefins. boiling above 250 F. as indicated by the bromine number.This excess of olens shows up disadvantageously in the road ratingtests. Along with the improvement in octane numbers 'of the gasolineproduct of the combined treatment is the improvement in road rating asmay be shown by road tests. A further improvement is one of economicsrather than in product. .It is quite obvious that it would be muchcheaper to have only one catalytic treating unit rather than two for thetreatment of the gas oil and naphthenic naphtha separately.

Although the processV has been described and exemplified in terms of itspreferred modications, it is understood that various changes may be madewithout departing from the spirit and scope of the disclosure and of theclaims.

We claim:

l. A process for the manufacture of a superior road rating motor fuel,which comprises forming a mixture of naphthenic naphtha boiling within arange of 250 to 400 F. and gas oil boiling within a range of 450 to '750F., said naphthenic naphtha and gas oil being mixed in a ratio withinthe range of 1:5 to 5:1, contacting said mix' ture with a. bauxitecatalyst at a temperature in the range of 900 to 1050o F. and a pressurein the range of 0 to 300 pounds per square inch so as to produce aneiiiuent, the gasoline fraction of which consists of a low-boiling halfcomprising primarily olens and a higher boiling half comprisingprimarily aromatics and naphthenes, and recovering said gasolinefraction as a product of the process.

2. A process for the manufacture of an improved road rating gasolinemotor fuel, which comprises forming a mixture of naphthenic naphthaboiling within a range of 250 to 400 F., gas oil boiling within a rangeof 450 to 750 F., and an inert diluent, said naphthenic naphtha and gasoil being mixed in a ratio Within the range of 1:2 to 2:1, preheatingsaid mixture to a temperature in the range of 900 to 1050o F., contact-3. A process for the manufacture oi an improved road rating gasolinemotor fuel, which comprises forming a mixture of naplithenic naphthaboiling in the range of 250 to 400 F., a virgin gas oil boiling in therange of 450 to 750 F., and steam diluent, said naphtlienic naplitha andVirgin gas oil being mixed in a ratio in the range of 1:2 to 2:1,preheating said mixture to a temperature in the range of 900 to 1050 F.,contacting said mixture with a bauxite catalyst at a pressure in therange of 20 to 100 pounds per square inch and a liquid space velocity of0.5 to 5 Volumes per volume of catalyst per hour so as t0 produce aneilluent, the gasoline fraction of which consists of a 10W-boiling halfcomprising primarily oleiins and a higher boiling half comprisingprimarily aromatics and naplitlienes, and recovering said gasolinefraction as a product of the process.

4. A process according to claim l., wherein a steam diluent is usedalong with said naphthenic naplatlia and said gas oil.

' PAUL HILTON JOHNSON.

GLENN J. FORSETH.

REFERENCES CITED The following references are or record in the file ofthis patent: Y

UNITED STATES PATENTS Number Name Date '2,283,854 Friedman et al May 19,1942 2,385,325 Bailey Sept. 25, 1945 2,404,595 Richker et al July 23,1946 2,406,112 Schulze Aug, 20, 1946 OTHER REFERENCES ChemicalConstituents of Petroleum, by Sachanen (pages 1.97 and 200), ReinholdPub; Corp., N. Y., 1945.

1. A PROCESS FOR THE MANUFACTURE OF A SUPERIOR ROAD RATING MOTOR FUEL,WHICH COMPRISES FORMING A MIXTURE OF NAPHTHENIC NAPHTHA BOILING WITHIN ARANGE OF 250 TO 400* F. AND GAS OIL BOILING WITHIN A RANGE OF 450 TO750* F., SAID NAPHTHENIC NAPHTHA AND GAS OIL BEING MIXED IN A RATIOWITHIN THE RANGE OF 1:5 TO 5:1, CONTACTING SAID MIXTURE WITH A BAUXITECATALYST AT A TEMPERATURE IN THE RANGE OF 900 TO 1050* F. AND A PRESSUREIN THE